add EsqlCapabilities to skip tests on older versions that don't have this fix

Author: fang-xing-esql

x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RestEsqlTestCase.java

@@ -987,6 +987,10 @@ public void testDoubleParamsWithLookupJoin() throws IOException {
     }
 
     public void testMultipleBatchesWithLookupJoin() throws IOException {
+        assumeTrue(
+            "Requires new null alias ids for join with multiple batches",
+            EsqlCapabilities.Cap.REPLACE_MISSING_FIELD_WITH_NULL_NEW_ALIAS_ID_FOR_JOIN_AND_MULTIPLE_BATCHES.isEnabled()
+        );
         // Create more than 10 indices to trigger multiple batches of data node execution.
         // The sort field should be missing on some indices to reproduce NullPointerException caused by duplicated items in layout
         for (int i = 1; i <= 20; i++) {

x-pack/plugin/esql/qa/testFixtures/src/main/resources/lookup-join.csv-spec

@@ -1456,9 +1456,10 @@ emp_no:integer | language_code:integer | language_name:keyword
 multipleBatches
 required_capability: join_lookup_v12
 required_capability: remove_redundant_sort
+required_capability: replace_missing_field_with_null_new_alias_id_for_join_and_multiple_batches
 
 from *
-| rename city.country.continent.planet.name as message 
+| rename city.country.continent.planet.name as message
 | lookup join message_types_lookup on message
 | sort language_code, birth_date
 | keep birth_date

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/action/EsqlCapabilities.java

@@ -912,7 +912,12 @@ public enum Cap {
         /**
          * The metrics command
          */
-        METRICS_COMMAND(Build.current().isSnapshot());
+        METRICS_COMMAND(Build.current().isSnapshot()),
+
+        /**
+         * Create null alias with new id in ReplaceMissingFieldWithNull when there is lookup join with multiple batches.
+         */
+        REPLACE_MISSING_FIELD_WITH_NULL_NEW_ALIAS_ID_FOR_JOIN_AND_MULTIPLE_BATCHES;
 
         private final boolean enabled;